Use of remotely piloted aircraft in precision agriculture: a review

The objective of this review was to examine the current use of remotely piloted aircraft (RPA) in obtaining data to assist in the application of precision farming techniques and to exemplify successful situations of technology use. The RPA has applications for monitoring, mapping, vegetation index (VI) extraction, volume, plant height, among others, and has been studied in several agricultural crops, being support for decision making on agrochemical application, planting failure, accompaniment of growth favoring the increase of crop productivity. One of the potentialities evaluated through RPA is the use of VI, which may be extracted from digital images obtained by cameras that contain only the visible band. It may be an alternative for farmers who do not have access to RPA coupled with high-tech embedded sensors. Therefore, it is a tool that may contribute to the decision making, allowing the acquisition of high spatial and temporal resolution imagesEl objetivo de esta revisión fue examinar el uso actual de aeronaves pilotadas remotamente (RPA) en la obtención de datos para aplicaciones de la agricultura de precisión, ejemplificando situaciones exitosas de uso de la tecnología. La RPA tiene aplicaciones para monitoreo, mapeo, extracción de índice de vegetación (VI), volumen, altura de plantas, y ha sido estudiado en diversas culturas agrícolas, siendo soporte para toma de decisión sobre aplicación de agroquímicos, falla de plantación, acompañamiento del crecimiento y aumento de la productividad. Un potencial evaluadas por la RPA es el uso del VI, que puede ser extraído de imágenes digitales obtenidas por cámaras que contienen la banda visible. Siendo una alternativa para los agricultores que no tienen acceso a RPA acoplado a sensores de alta tecnología. Por lo tanto, es una herramienta que puede contribuir a la toma de decisiones, permitiendo la adquisición de imágenes de alta resolución espacial y tempora

Characterization of the Transverse Distribution of Fertilizer in Coffee Plantations

Considering the impact of fertilizers on coffee production costs, the search for greater efficiency in the use of these inputs has an important role. Accordingly, the aim of the present study is to evaluate the transverse distribution of fertilizer by a centrifugal spreader in a coffee plantation and to compare two operating modes: fertilizer application on one side (FA1), or both sides (FA2) of the coffee plants. In addition, three doses (200, 300 and 400 kg ha−1) of monoammonium phosphate and three spreading disk rotation speeds (240, 375 and 750 rpm) were tested. To characterize fertilizer distribution profiles, collectors were placed under the canopy of coffee plants, and the collected fertilizer was weighed. From the data obtained, distribution profile histograms were constructed, and coefficients of variation were calculated for each treatment. Distribution profiles with higher uniformity were related to the morphologic characteristics of the coffee plants. Regarding the operating modes evaluated, FA1 presented better results with a disk rotation speed of 750 rpm (FA1-W3); FA2 produced the best results with a disk rotation speed of 240 rpm. By relating these results with information on root morphology, FA1-W3 was found to be the most appropriate application method